Search results for "Transcranial"
showing 10 items of 413 documents
How to improve reading skills in dyslexics: the effect of high frequency rTMS.
2013
The latest progress in understanding remediation of dyslexia underlines how some changes in brain are a necessary mechanism of improvement. We wanted to determine whether high frequency repetitive transcranial magnetic stimulation (hf-rTMS) over areas that are underactive during reading in dyslexics, would improve reading of dyslexic adults. We applied 5Hz-TMS over both left and right inferior parietal lobule (IPL) and superior temporal gyrus (STG) prior to word, non-word and text reading aloud. Results show that hf-rTMS stimulation over the left IPL improves non-word reading accuracy and hf-rTMS stimulation over the left STG increases word reading speed and text reading accuracy. Moreover …
The what and how of observational learning
2007
Abstract Neuroimaging evidence increasingly supports the hypothesis that the same neural structures subserve the execution, imagination, and observation of actions. We used repetitive transcranial magnetic stimulation (rTMS) to investigate the specific roles of cerebellum and dorsolateral prefrontal cortex (DLPFC) in observational learning of a visuomotor task. Subjects observed an actor detecting a hidden sequence in a matrix and then performed the task detecting either the previously observed sequence or a new one. rTMS applied over the cerebellum before the observational training interfered with performance of the new sequence, whereas rTMS applied over the DLPFC interfered with performa…
Facilitation of bottom-up feature detection following rTMS-interference of the right parietal cortex
2010
In visual search tasks the optimal strategy should utilize relevant information ignoring irrelevant one. When the information at the feature and object levels are in conflict, un-necessary processing at higher level of object shape can interfere with detection of lower level orientation feature. We explored the effects of inhibitory trains of transcranial magnetic stimulation (rTMS) on the right and left parietal cortex in healthy subjects performing two visual search tasks. One task (Task A) was characterised by an object-to-feature interference. The other task (Task B) was without such interference. We found that rTMS of the right parietal cortex significantly reduced reaction times (RTs)…
Role of sensorimotor areas in early detection of motor errors: An EEG and TMS study
2019
Abstract Action execution is prone to errors and, while engaged in interaction, our brain is tuned to detect deviations from what one expects from other’s action. Prior research has shown that Event-Related-Potentials (ERPs) are specifically modulated by the observation of action mistakes interfering with goal achievement. However, in complex and modular actions, embedded motor errors do not necessarily produce an immediate effect on the global goal. Here we dissociate embedded motor goals from global action goals by asking subjects to observe familiar but untrained knotting actions. During knotting an embedded motor error (i.e. the rope is inserted top-down instead of bottom-up during the …
Taking both sides: do unilateral anterior temporal lobe lesions disrupt semantic memory?
2010
The most selective disorder of central conceptual knowledge arises in semantic dementia, a degenerative condition associated with bilateral atrophy of the inferior and polar regions of the temporal lobes. Likewise, semantic impairment in both herpes simplex virus encephalitis and Alzheimer's disease is typically associated with bilateral, anterior temporal pathology. These findings suggest that conceptual representations are supported via an interconnected, bilateral, anterior temporal network and that it may take damage to both sides to produce an unequivocal deficit of central semantic memory. We tested and supported this hypothesis by investigating a case series of 20 patients with unila…
Low-frequency transcranial magnetic stimulation in patients with cortical dysplasia: A preliminary study
2003
no abstract available
Transcranial Doppler ultrasound study of the effects of nitrous oxide on cerebral autoregulation during neurosurgical anesthesia: a randomized contro…
2003
Object. Nitrous oxide has an adverse effect on cerebrovascular hemodynamics. Increased intracranial pressure, cerebral blood flow (CBF), cerebral metabolic rate of O2 (CMRO2), and reduced autoregulation indices have been reported, but their magnitudes are still being debated. This study was designed to evaluate the effect of N2O on CBF and autoregulatory indexes during N2O—sevoflurane anesthesia in a prospective randomized controlled series of patients. Methods. Two groups of 20 patients were studied on the basis of the use of N2O in the anesthetic gas mixture. The transient hyperemic response test, which relies on transcranial Doppler ultrasound techniques, was used to assess cerebral hemo…
Echogenicity of the substantia nigra in relatives of patients with sporadic Parkinson’s disease
2003
Increased echogenicity of the substantia nigra (SN) on ultrasound is a typical sonographic finding in Parkinson's disease (PD). Sonographic signal intensity of the SN is related to tissue iron content with higher iron level being associated with increased echogenicity. Recent findings indicate that hyperechogenicity of the SN represents an important susceptibility factor for nigrostriatal degeneration. In this study we determined the prevalence of a characteristic ultrasound sign of Parkinson's disease in first-degree relatives of PD patients. Fourteen patients with sporadic PD and 58 of their relatives underwent neurological, neuropsychological, and ultrasound examination. In addition, fou…
Acceptability, attitudes and knowledge towards Transcranial Magnetic Stimulation (TMS) among psychiatrists in France
2020
Abstract Background Non-invasive brain stimulation techniques are becoming a part of psychiatrists’ therapeutic arsenal. Proof of TMS effectiveness and its indications are becoming clearer. While international recommendations exist, and many countries have already recognized the use of these techniques, the French situation is peculiar since no recommendation has been published by the High Authority of Health. Consequently, those techniques are not reimbursed by the healthcare service, few practitioners are trained, some are criticized for using it, and practices remain very heterogeneous. It is therefore important to investigate what slows down the development of these techniques. The obje…
Training the Motor Cortex by Observing the Actions of Others During Immobilization
2014
International audience; Limb immobilization and nonuse are well-known causes of corticomotor depression. While physical training can drive the recovery from nonuse-dependent corticomotor effects, it remains unclear if it is possible to gain access to motor cortex in alternative ways, such as through motor imagery (MI) or action observation (AO). Transcranial magnetic stimulation was used to study the excitability of the hand left motor cortex in normal subjects immediately before and after 10 h of right arm immobilization. During immobilization, subjects were requested either to imagine to act with their constrained limb or to observe hand actions performed by other individuals. A third gro…